JPH056282U - Spiral duct - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention has an object to obtain a spiral duct having a high compression rate, a strong external pressing resistance force, and a meshing goby that is not separated during extension. According to the present invention, a thin metal plate 4 is formed by alternately arranging outer curved portions 1 and inner concave curved portions 2 and providing several corrugated ribs 3 between the curved portions 1 and the concave curved portions 2. In forming a spiral duct of spiral shape by spirally winding, female and male gobys 5 and 6 for engaging the metal sheet 4 with outer curved portions 1 on both side edges of the metal sheet 4 are formed. It is a spiral duct characterized by being formed in a curved shape in the same row.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention is a spiral duct that can be expanded and contracted, and more specifically, a male and female goby is formed so that it has the same shape and shape as the outer curved part, and has a large compression ratio and prevents the meshing goby from separating during extension. It is about ducts.

[0002]

[Prior Art]

 Japanese Patent Publication No. 3-17105 discloses a spiral duct of this type.

In this publication, a spiral duct a is formed by spirally winding an edge of a thin metal plate having a predetermined width while making a goth-matching 1 to form a cylindrical body. Several corrugated ribs 2 ... 2 are formed at the positions, and these corrugated ribs 2 ... 2 are closely contacted so as to be freely expandable and contractable, and the corrugated ribs 2 ... When the two are brought into close contact with each other, the inner and outer ends of these corrugated ribs 2 ... 2 are bent so that the bent tips become substantially linear, and the side wall surface portions of the corrugated ribs 2 ... It describes a spiral duct in which the wall surfaces facing each other are closely contacted with each other so that a space is not practically formed in the corrugated rib portion.

[0004]

[Problems to be solved by the device]

 However, in this publication, since the gobys 1 and 1 are provided in the middle of the corrugated ribs 2 and 2 in a flat plate shape, when the spiral duct is compressed, the goby 1 and 1 parts maintain their original shape and thus the partial contraction occurs. There is a problem that the dimension ratio is hindered, and when the spiral duct is stretched in both directions, the flat-shaped goby 1, 1 is deformed in the direction of the arrow as shown in FIG. .

[0005]

[Means for Solving the Problems]

 In the present invention, the outer curved portion 1 and the inner curved portion 2 are alternately arranged in parallel, and a corrugated rib 3 is provided between the curved portion 1 and the concave curved portion 2 to form a thin metal plate 4 in a spiral shape. In forming the spiral duct which can be wound and expanded and contracted, the male and female goby 5 and 6 for engaging the metal thin plate 4 with the outer curved portions 1 on both side edges of the metal thin plate 4 are formed in the same row. It is intended to solve such a problem by forming a curve at the eggplant position.

[0006]

【Example】

 Embodiments will be described below with reference to the drawings.

Male and female goby 5 and 6 are formed on both side edges of a long metal thin plate 4 having a plurality of corrugated ribs 3 between the outer curved portions 1 and the inner concave portions 2 alternately arranged. The gobs 5 and 6 are provided at the positions of the outer curved portions 1 on both sides so as to be in the same row as the outer curved portion 1.

The long thin metal plate 4 thus formed is spirally wound while the male and female halves 5 and 6 are engaged with each other to form the expandable and contractible spiral duct 7.

The spiral duct 7 thus formed is compressed and reduced to a length of 1/3 or less, stored and transported, and then stretched or bent at a construction site for use.

[0010]

[Effect of the device]

 As described above, according to the present invention, the male and female gobies are provided in the same row and the same shape as the outer curved portions on both side edges of the thin metal plate. The ribs come into contact with each other like the corrugated ribs of other parts, and the reduction ratio of the spiral duct can be improved, and the resistance to external pressure and impact is dramatically improved. This has the effect of preventing damage to the duct.

Further, even when the male and female goby are extended, they are located outside the spiral duct and are meshed with each other in an arc shape, so that there is an effect that separation due to deformation or the like does not occur.

[Brief description of drawings]

FIG. 1 is a partially omitted side view showing a spiral duct of the present invention in a reduced size.

FIG. 2 is an enlarged cross-sectional view of a thin metal plate.

FIG. 3 is an enlarged vertical sectional view of a male and female goby portion.

FIG. 4 is a partial sectional view of the spiral duct of the present invention when extended.

FIG. 5 is a cross-sectional view showing a separation phenomenon when a conventional goby is elongated. The arrow indicates the direction of deformation due to tension.

[Explanation of symbols]

 1 is an outer curved portion 2 is an inner concave portion 3 is a rib 4 is a thin metal plate 5 and 6 is a male and female goby 7 is a spiral duct

Claims (1)

[Claims for utility model registration] [Claim 1] The outer curved portion 1 and the inner curved portion 2 are alternately arranged in parallel, and several corrugated ribs 3 are provided between the curved portion 1 and the concave portion 2. When forming the spiral duct of the expandable and contractible cylindrical body by spirally winding the provided metal thin plate 4, the male and female goby 5 and 6 for engaging the metal thin plate 4 are provided on both side edges of the metal thin plate 4. A spiral duct characterized by being formed at a position in the same row as the outer curved portion 1 of the above.